WASHINGTON (CNN) -- Former Black Panther Mumia Abu-Jamal, convicted of gunning down a Philadelphia police officer 27 years ago, deserves a new hearing to determine whether he should be executed for his crime, a federal appeals court ruled Thursday.
Mumia Abu-Jamal was convicted in 1982 of killing a police officer the year before.
A jury had originally imposed the capital sentence, and the case has since attracted international attention stemming from allegations of prosecutorial misconduct.
But the three-judge panel of the U.S. Court of Appeals for the 3rd Circuit kept the 1982 murder conviction in place. The court upheld a 2001 ruling that tossed out the death penalty because the jury was improperly instructed.
Prosecutors have the choice of appealing the sentence reduction to the Supreme Court, while Abu-Jamal can ask the high court to review his original conviction.
lf the ruling is not overturned on appeal, federal prosecutors would have to decide whether to conduct a new death penalty sentencing hearing or allow Abu-Jamal to spend the rest of his life behind bars.
The 53-year-old onetime radio reporter and cab driver has been divisive figure, with many prominent supporters backing his contention that he was a victim of racism at his trial.
Others have countered Abu-Jamal is using skin color to escape responsibility for his actions, and say he has divided the community for years with his provocative writing and activism.
He was convicted of the December 9, 1981, murder of Officer Daniel Faulkner, 25, in Philadelphia. Faulkner had pulled over Abu-Jamal's brother in a late-night traffic stop. Witnesses said Abu-Jamal, who was nearby, ran over and shot the policeman in the back and in the head.
Abu-Jamal, once known as Wesley Cook, was also wounded in the encounter and later confessed to the killing, according to other witnesses who testified at trial.
Abu-Jamal is black, the police officer was white.
A jury of 10 whites and two blacks convicted him of capital murder and sentenced him to death.
In his appeal, Abu-Jamal claimed prosecutors acted in a "racially discriminatory manner" by unfairly keeping more blacks off the jury.
The federal appeals court ultimately concluded the jury was improperly instructed on how to weigh "mitigating factors" offered by the defense that might have kept Abu-Jamal off death row.
Pennsylvania law at the time said jurors did not have to unanimously agree on a mitigating circumstance, such as the fact that Abu-Jamal had no prior criminal record.
"We conclude that the verdict form together with the jury instructions were misleading as to whether unanimity was required in consideration of mitigating circumstances," wrote the appeals court.
Pennsylvania officials argued that Abu-Jamal waited too long to raise these objections when his claims were first thoroughly reviewed in a 1995 state appeal.
The federal appeals court focused mostly on the jury instruction issue, but contentious oral arguments last May also dealt with the trial jury's racial makeup. Faulkner's widow and Abu-Jamal's brother attended, and protests on both sides were held outside the courtroom in downtown Philadelphia.
Abu-Jamal's lawyer, Robert Bryan, had argued "a culture of discrimination" made a fair trial impossible. There was no immediate comment from him, or from Philadelphia County's district attorney, on Thursday's decision.
Since his conviction, Abu-Jamal has written extensively about his case and other issues from behind bars. Many prominent groups and individuals, including singer Harry Belafonte, the NAACP, and the European Parliament, are cited on his Web site as supporters.
The slain officer's widow, Maureen Faulkner, has recently written a book about her husband and the case, "Murdered by Mumia: A Life Sentence of Loss, Pain and Injustice." E-mail to a friend